1. Field of the Invention
The present invention relates to a distributed processing system constructed so that a shared file system can be directly accessed by each of a plurality of computers (nodes) in a network environment.
2. Related Background Art
A distributed processing system for distributing processes to a plurality of nodes is provided for a UNIX system. This type of distributed processing system must keep a consistency (matching characteristic) of the data to be processes by the respective nodes as the whole distributed processing system, and hence it is undesirable that two or more pieces of the same data exist within the distributed processing system. Accordingly, a device for storing the data existing in a unique location within the distributed processing system is required to be accessible from each of the nodes. For this purpose, there is a shared file system for sharing one single disk or a plurality of disks (which will hereinafter be referred to as a xe2x80x9cshared diskxe2x80x9d) physically or logically partitioned with the respective nodes within the distributed processing system.
In this type of shared file system, it is required for each node to register identification information of all shared disks configuring the shared file system and identification information of all nodes sharing the shared file system in a shared file system management file in itself, to register, into each shared disk, its own identification information and the device identification information which the node itself uses to access the shared disk, and thereafter to mount the shared file system, by activating cluster service. Further, if the number of the nodes utilizing the shared file system increases or decreases, if such a node changes, or if the number of the shared disks configuring the shared file system increases or decreases, each of the nodes must set each/shared disk in an unmount state by temporarily stopping the cluster service, and thereafter update the shared file system management file and the identification information registered in each of the shared disks.
The operation for the shared file system described above, however, must be executed in each node. While on the other hand, a content of this operation must be consistent throughout the distributed processing system as a whole. Namely, with respect to same shared file system, the contents registered in the shared file system management file of a certain node must be same as that of other node. Therefore a system manager of the distributed processing system must have executed respectively the operation of the same content with respect to the shared file system in each of the nodes. Thus, the shared file system used in the conventional distributed processing system had no contrivance for facilitating the operation for the shared file system.
It is a primary object of the present invention, which was devised under such circumstances to obviate the above problems, to provide a distributed processing system capable of executing an operation for a shared file system used in the distributed processing system on the basis of a command inputted to one node, an apparatus for operating a shared file system that is included in the node in this distributed processing system, and a computer readable medium stored with a program for making a computer function as the shared file system operating apparatus.
To accomplish the above object, according to a first aspect of the present invention, a distributed processing system is constructed of a plurality of nodes and at least one storage device connected to each other under a network environment. The individual node includes a storage unit for retaining a management file defining identification information of storage devices configuring a shared file system, and identification information of the nodes sharing the shared file system, and a control module for updating the definitions in the management file. The control module of at least one of the nodes indicates the control module of each of the nodes to update the definition in the management file retained in each of the storage units in accordance with a command inputted by an operator.
According to a second aspect of the present invention, a distributed processing system is constructed of a plurality of nodes and at least one storage device connected to each other under a network environment. The individual node includes a first storage unit for retaining a management file defining identification information of a storage device configuring a shared file system and identification information of the nodes sharing the shared file system, a second storage unit for retaining mount information for indicating whether or not the shared file system corresponding to the identification information of a storage device defined by the management file is mounted to its own node, and a control module for updating the definitions of the mount information. The control module of at least one of the nodes indicates the control module of each of the nodes to update the mount information retained in each of the second storage units in accordance with a command inputted by an operator.
In thus constructed distributed processing system according to the present invention, when the operator inputs the command to the node having the function of indicating the updating, the control module of this node indicates the control module of each of the nodes to execute an operation of the shared file system. To be specific, the control module gives the indication of updating the management file defining the shared file system, or the mount information indicating whether or not the shared file system defined by this management file is mounted to its own node. When receiving this indication, the control module of each node executes the operation for the shared file system in accordance with the indication. Accordingly, the operation for the shared file system is completed as the whole distributed processing system simply by the operator""s inputting the command a single node.
According to the present invention, only a specified node in the distributed processing system may have the control module for indicating each node to execute the operation (updating the management file or the mount information) for the shared file system, or all the nodes in the distributed processing system may have this control modules. Further, it is desirable that the control module for indicating each node to execute the operation (updating the management file or the mount information) for the shared file system, gives the indication to itself, in other words, that the control module executes the operation of updating the management file within its storage unit, or of updating the mount information within its second storage unit.
Note that only one storage device or a plurality of storage devices may be provided in the distributed processing system. In the case that there are plurality of devices, a part (one or a plurality) of the storage devices among those storage devices may configure the shared file system, or all the storage devices may configure the shared file system. If the plurality of storage devices configure the shared file system, the identification information of the plurality of storage devices are respectively defined in the management file. It is to be noted that each of the storage devices may be one piece of disk or may be a partition defined by logically partitioning a storage area on one single disk, irrespective of whether it or they may configure the shared file system or not. Further, a storage device configuring the shared file system and another storage device that does not configure it may be physically constructed on a single of disk or may be constructed in a disk device having the plurality of disks.
Each of the storage devices configuring the shared file system is stored with a device identification number used when each of the nodes sharing the shared file system accesses the same storage device. The control module for indicating each node to execute the operation (updating the management file or the mount information) of the shred file system, may update the device identification number stored in the storage device by itself, or may indicate the control module of other node to update the device identification number stored in each storage device.
According to a third aspect of the present invention, an apparatus for operating a shared file system in a node configuring a distributed processing system together with other nodes and at least one storage device comprises a storage unit retaining a management file for defining identification information of a storage device configuring a shared file system, and identification information of the nodes sharing the shared file system, and a control module for indicating other nodes configuring the distributed processing system and having the storage unit, to update the management file stored in respective storage unit of each node in accordance with a command inputted by an operator.
According to a fourth aspect of the present invention, an apparatus for operating that shared file system comprises a first storage unit for retaining a management file defining identification information of a storage device configuring a. shared file system, and identification data of the nodes sharing the shared file system, a second storage unit for retaining mount information indicating whether or not the shared file system corresponding to the identification information of storage devices defined by the management file is mounted to its own node, and a control module for indicating other nodes configuring the distributed processing system and having the first and second storage units, to update the mount information retained in each of the second units in accordance with a command inputted by an operator.
According to a fifth aspect of the present invention, there is provided a computer readable medium stored with a program for making a computer configuring a distributed processing system together with other computers and at least one storage device under a network environment execute a step of retaining a management file defining identification information of a storage device configuring a shared file system and identification information of the computers sharing the shared file system, and a step of indicating each of other computers configuring the distributed processing system to update the management file retained by each of the computers in accordance with a command inputted by an operator.
According to a sixth aspect of the present invention, there is provided a computer readable medium stored with a program for making a computer configuring a distributed processing system together with other computers and at least one storage device under a network environment execute a step of retaining a management file defining identification information of a storage device configuring a shared file system and identification information of said computers sharing the shared file system, a step of retaining mount information for indicating whether or not the shared file system corresponding to the identification information of a storage device defined by the management file is mounted to its own computer, and a step of indicating each of other computers configuring the distributed processing system to update the mount information retained by each of the computers in accordance with a command inputted by an operator.